That is a great letter.
As a father of a child with Downs - everytime I hear or read about someone using the word, it just stings. I have family members who still use it, so there is a long way to go.
In all honesty, I used the word in the past before I was blessed with my boy. The author of the letter is right - if people could see how hard my son and others with challenges work every day, people would never use that word in a deragatory way again.
Nothing is easy for him but he tries so damn hard... DS kids are really special, as are others.
As for Ms. Coulter, I dont know if she needs to apologize as much as disappear. She, Maher, Maddow, Limbaugh, etc... they are just nasty people who really ruin the political discourse.